today Ray-Ban has a sale on. it seems all sunglasses are £16.88 on their website. unless the link I looked at took me to a scam site.
also it was quite surprising to see all the sunglasses banner ads once i'd clicked on this thread.

Bloc customer service is top notch too. I've got a pair of Bloc Shifters with the changeable lenses. In a standard moment of clumsy buffoonery I managed to snap the frames, so emailed them to see if I could buy a new set without having to buy all the lenses too. They sent me a new set for nowt. Which was nice of them